Stereotactic neurosurgery is a field of neurosurgery in which a probe is advanced through a burr hole to a target of interest by means of a mechanical device attached to the skull with aiming based on pre-operative images. The probe may be a biopsy needle or an implantable device, but it is geometrically rigid, so that its tip can be brought to a target of interest specified on a pre-operative image, by means of a geometrical calculation. In the past, large metal frames that encompass the entire head of a patient were used with the attachment of small platforms placed over an entry site. Conventional metal frames are designed for approaching one target at a time with an unrestricted entry point towards the deep target, by employing the principle that the target is at the center of a sphere. Because of the long trajectories involved, both accuracy and patient comfort are challenged by the demands of surgeries for deep brain stimulation (DBS) in which the patients are awake throughout the lengthy surgical procedure.
Other conventional approaches require the attachment of bone-implanted fiducials, the subsequent acquisition of a preoperative tomogram, and intraoperative optical tracking to aim a probe at its target. However, there are problems regarding geometrically stability, limited space for access to the burr hole and surgical manipulation, which requires a time-consuming process of aiming and locking on the target. Access to the burr hole is crucially important for the purpose of stopping bleeding from the bone cavity, dura, and the surface of the cortex during the procedure. In some conventional devices, a medical professional conducts the aiming process by watching a guiding icon on the screen of the intraoperative tracking system and then locking a guiding platform into place with one hand, while it is held at the correct trajectory with the other hand. The trajectory is two-dimensional, meaning that there are two mutually-perpendicular angular adjustments required, each of which must be set simultaneously for the correct trajectory. Finding the correct trajectory via the guiding icon is time consuming because of the difficulty of making fine adjustments of one angle of the approach without changing the other angle. A further difficulty with this aiming procedure is maintaining both angles of the correct trajectory while locking the device on target. The locking step can be especially frustrating to a medical processional if either angle is changed inadvertently during locking, as revealed by the guiding icon, and as a result, the device must be unlocked and the adjustment started again from the beginning Several iterations may be required, resulting in wasted operating time. In other conventional approaches, a custom apparatus may be built for each particular patient, after preliminary scans of the target area of interest have been taken to obtain specific dimensional and anatomical data for the particular patient. However, following a preliminary scanning procedure, a patient must wait several days or weeks until the custom frame has been built and delivered, and even upon setting up the custom frame in preparation for a surgical procedure, fine-tuning is required to further adjust the apparatus to address intraoperative challenges faced by medical professionals performing the surgical procedure.
Among other needs, there exists a need for adjustable surgical means that can be quickly and accurately configured to provide for varying positions and trajectories for a particular procedure and corresponding particular patient anatomy, and which can intraoperatively guide surgical instruments with accuracy at the desired settings.
Therefore, a heretofore unaddressed need exists in the art to address the aforementioned deficiencies and inadequacies.